Method and ethephon-based composition for controlling plant growth

ABSTRACT

Ethephon-based composition for the regulation of plant growth containing in addition to ethephon, at least one product or adjuvant the chemical structure of which contains at least two acid functions selected from carboxylic acid type of formula (--COOH) and phosphonic acid type of formula (--PO 3  H 2 ), at least one of these acid functions being the (--PO 3  H 2 ) function.

This application is a 371 of PCT/FR96/00018 filed Jan. 4, 1996.

A subject of the invention is a process for the regulation of plantgrowth, this process using ethephon.

It also relates to an ethephon-based composition for the regulation ofplant growth.

It should be noted that ethephon, or 2-chloroethyl-phosphonic acid, is aplant growth regulator which is presented in the form of an acid greysolid, melting at about 74-75° C.; its high solubility in water allowsit to be handled more conveniently, without isolating it, in the form ofa concentrated solution of about 1000 g/l.

It is presumed that its biological activity is linked to the emission ofethylene, outside and/or inside plants and to the fact that it probablytriggers an endogenic emission of ethylene in the plant via a cascadeeffect. As a growth regulator, it can be used to provoke ripening offruits and vegetables, to reduce the length of stems and straw ofcereals, to encourage the axillary or apical budding of certain flowersand to increase the production of latex during the tapping of rubberplants.

Ethephon also encourages the early and uniform opening of ripe cottonboll and provokes the senescence of leaves or even their fallingdepending on the conditions of the medium, which facilitates harvesting.

Document GB-A-1 505 331 already discloses compositions comprising on onehand a compound providing ethylene and on the other hand a chelatingagent.

Moreover, the prior art documents DD-A-237 253 and DD-A-139 063 disclosecompositions comprising ethephon and a compound constituted by ahydrocarbonated chain having one carbon atom, bisubstituted by twophosphonic acid functions.

Within the scope of its research directed with a view to making betteruse of the biological properties of a compound constituted by ahydrocarbonated chain with one carbon atom, bisubstituted by twophosphonic acid functions.

Within the scope of its research directed with a view to making betteruse of the biological properties of ethephon, in other words obtainingquicker or more intense biological effects for a given quantity ofactive ingredient, the Applicants had the merit of discovering that thisgoal could unexpectedly and surprisingly be achieved when ethephon wasused in a concomitant fashion with at least one of the substances of agroup of products known until now for properties exhibited in technicalfields as removed from agriculture as the fluidification of cements,softening and detergent treatment of textiles, the formation ofchelating agents with multivalent metals or also the treatment offeed-water for boilers, the chemical structure of these products whichcan be conveniently designated by the term "adjuvants" beingcharacterized by the presence of at least two acid functions chosen fromthe group containing acid functions of carboxylic type of formula(--COOH) and those of phosphonic type (--PO₃ H₂), at least one of theseacid functions being the (--PO₃ H₂) function, these acid functions beingconnected by optionally substituted carbon chains defined hereafter.

It follows that the plant growth regulation process according to theinvention is characterized in that on the plants to be treated there isused ethephon and at least one product, the chemical structure of whichis characterized in that it contains at least two acid functions chosenfrom the group containing acid functions of carboxylic type of formula(--COOH) and those of phosphonic type (--PO₃ H₂), at least one of theseacid functions being the (--PO₃ H₂) function, said product beingselected from the group comprising

that having the formula ##STR1## and those in which the acid functionsare connected by an organic chain of (--R--O--R) type containing anether function and in which R represents a linear or branchedhydrocarbon chain containing from 2 to 6 carbon atoms and optionally oneor more substituents of hydroxyl type (--OH) and/or halogen and/orhydroxyethyl (--CH₂ --CH₂ --OH) and/or phenyl (--C₆ H₅) and/orhydroxyphenyt (--C₆ H₄ --OH), the two chains R can be identical to ordifferent from each other,

and/or an organic chain of (--R--NH--R) type containing a secondaryamine function and in which R is defined as above, the two chains R canbe identical to or different from each other,

and/or an organic chain of ##STR2## type containing two tertiary aminefunctions and in which R is defined as above, the two chains R can beidentical to or different from each other,

and/or by a chain of ##STR3## type in which (--R') represents hydrogenor the afore-mentioned chain R, and/or by an organic chain of ##STR4##type containing a tertiary amine function in which R is defined asabove, the three chains R can be identical to or different from eachother.

The composition according to the invention based on ethephon for theregulation of plant growth is characterized in that it contains, inaddition to ethephon and, if necessary, the usual constituents ofethephon-based compositions, at least one product or adjuvant thechemical structure of which contains at least two acid functions chosenfrom the group containing acid functions of carboxylic type of formula(--COOH) and those of phosphonic type (--PO₃ H₂), at least one of theseacid functions being the (--PO3H2) function, said product being selectedfrom the group comprising

that having the formula ##STR5## and those in which the acid functionsare connected by an organic chain of (--R--O--R) type containing anether function and in which R is defined as above, the two chains R canbe identical to or different from each other,

and/or an organic chain of (--R--NH--R) type containing a secondaryamine function and in which R is defined as above, the two chains R canbe identical to or different from each other,

and/or an organic chain of ##STR6## type containing two tertiary aminefunctions and in which R is defined as above, the two chains R can beidentical to or different from each other,

and/or by a chain of ##STR7## type in which (--R') represents hydrogenor the aforementioned chain R, and/or by an organic chain of ##STR8##type containing a tertiary amine function in which R is defined asabove, the three chains R can be identical to or different from eachother, at least one of these acid functions being the (--PO₃ H₂)function.

According to an advantageous implementation of the process andcomposition according to the invention, the product or adjuvant ischaracterized in that its chemical structure, which contains at leasttwo acid functions, is represented by one of the general formulaeindicated hereafter: ##STR9## or ##STR10## in which n represents aninteger from 0 to 4,

R₂ represents a linear or branched hydrocarbon group having 2 to 6carbon atoms,

R₁ represents, independently at each occurrence, a hydrogen atom, analkyl chain having 1 to 4 carbon atoms, a phenyl group, a hydroxyphenylgroup, a hydroxyalkyl group, an alkylene-phosphonic acid group or one ofthe five groups represented below:

    --CH.sub.2 --CH.sub.2 --NH--PO.sub.3 H.sub.2 ##STR11##

    --CH.sub.2 --COOH

(the number of --CH₂ COOH groups being at most three) ##STR12##

According to another advantageous implementation of the process andcomposition according to the invention, the product or adjuvant ischaracterized in that its chemical structure, which contains at leasttwo acid functions, is represented by the formula ##STR13## in which nrepresents an integer equal to 0 or 1,

X and Y represent a hydrogen atom or an alkyl group having 1 to 6 carbonatoms,

R₃ represents a hydrogen atom, an aliphatic hydrocarbon group, ahalo-substituted aliphatic hydrocarbon group, a hydroxy-substitutedaliphatic hydrocarbon group, the --CH₂ COOH group or the ##STR14## groupin which m represents an integer from 1 to 6,

X and Y represent a hydrogen atom or an alkyl group,

Z represents a hydrogen atom or the ##STR15## group Z' represents Z orthe group of formula ##STR16## in which b is an integer from 1 to 6.

According to another advantageous implementation of the process andcomposition according to the invention, the product or adjuvant ischaracterized in that its chemical structure, which contains at leasttwo acid functions, is represented by the formula ##STR17## i.e. isconstituted by an alkyl-diphosphonic acid, X_(a) being chosen from thegroups containing hydrogen or short alkyl groups having 1 to 4 carbonatoms,

Y_(a) being chosen from the groups containing hydrogen, a hydroxylradical, a halogen radical, short alkyl groups containing 1 to 4 carbonatoms,

n being an integer from 2 to 6.

According to another advantageous implementation of the process andcomposition according to the invention, the product or adjuvant ischaracterized in that its chemical structure, which contains at leasttwo acid functions, is represented by the formula ##STR18## in which R"represents hydrogen or a short alkyl chain having 1 to 4 carbon atoms,

R"' represents hydrogen or a methyl group, the products corresponding toformulae ##STR19## and ##STR20## being more particularly preferred.

According to another advantageous implementation of the process andcomposition according to the invention, the product or adjuvant ischaracterized in that its chemical structure, which contains at leasttwo acid functions, is represented either by the formula ##STR21## inwhich n is an integer from 1 to 5, or by the following products:1,6-hexylenediamine-N,N,N',N' tetrakis((methylene)-phosphonic) acid,

ethylenediamine-N,N,N',N'-tetrakis((methylene)-phosphonic) acid,

diethylenetriamine-N,N,N',N",N"-penta((methylene)-phosphonic) acid,

nitrilo-N,N,N-tris((methylene)-phosphonic) acid which are particularlypreferred.

According to another advantageous implementation of the process andcomposition according to the invention, the product or adjuvant ischaracterized in that its chemical structure, which contains at leasttwo acid functions, is represented by one of the formulae ##STR22##

From a more general point of view, the products or adjuvants used in aconcomitant fashion with ethephon and identified above areadvantageously used in the form of alkaline and/or alkaline-earth saltsand/or of salts of amines having 2 to about 18 carbon atoms, theseamines being optionally oxyethylenated and/or oxypropylenated, oncondition that the pH of the final composition, if it is an aqueous orhydroalcoholic solution, does not exceed 3.

In the composition according to the invention, the ethephon/adjuvantweight ratio is from 10/1 to 1/10, preferably 5/1 to 1/5.

The composition can be presented in the form of an aqueous solutioncontaining one or more wetting agents chosen from the C₄ to C₁₈ alcoholsand/or oxyethylenated and/or oxypropylenated alkylphenols the alcoholfunction of which at the end of the chain is optionally substituted byan oxyacetic group or a chlorine atom, alkylglucosides, alkanesulphonicand/or alkylarylsulphonic acids, these last-named can be partially ortotally neutralized in the form of alkaline and/or alkaline-earth saltsand/or of salts of amines having 2 to about 18 carbon atoms, theseamines being optionally oxyethylenated and/or oxypropylenated, oncondition that the pH of the composition does not exceed 3.

It can also be presented in the form of a powder containing one or morewetting agents chosen from those identified above and an absorbentsupport which is soluble in water, such as dextrin or maltodextrin, orinsoluble in water such as micronized silica, it being understood that,in the latter case, dispersants can be resorted to such aslignosulphonates or polynaphthylmethane-polysulphonates.

Finally, it can be presented in the form of spreadable granulescontaining one or more wetting agents chosen from those identified aboveand an absorbent support which is either soluble in water, such asgraded dextrin or maltodextrin, or insoluble in water such as gradedsilicates, in particular Sepiolite®.

The compositions according to the invention can be applied on plants indifferent ways according to the presentation method.

For example, when these compositions are aqueous solutions, solublepowders, wettable powders or emulsionnable concentrates, dispersible orsoluble granules, the plant protection mixture--a term designating thedilution ready to be sprayed on the plants to be treated--is prepared bysimply diluting the composition in one part of the water envisaged forthe treatment, then by topping up, under stirring, with water to thedesired volume.

When these compositions are in the form of spreadable granules, dustingpowder or tablets, the composition is spread directly on the soil orplaced directly in contact with the plant to be treated, for example inthe crown of the pineapple in order to act on its flowering.

According to an advantageous implementation of the process according tothe invention, 20 g to 3000 g of ethephon combined with 20 to 5000 g ofone or more of the products or adjuvants identified above are appliedper hectare according to the cultivation, the physiological stage andthe effect sought, the assembly constituted by ethephon and the adjuvantcan be diluted in water at the rate of 20 to 3000 liters of water perhectare.

The ethephon can be applied plant by plant and the doses are very weakper plant (rubber plants, pineapples . . . ) or by way of a plantprotection mixture or slurry. In the latter case, depending on theapplication methods, 20 to 3000 liters of water containing 20 to 3000 gof ethephon and 20 to 5000 g of adjuvant can be sprayed per hectare.

The products or adjuvants identified above and used in the process orthe composition according to the invention are products known inthemselves but for applications extremely distant from those envisagedby the present invention.

In that connection,

certain of these products are those described in the Patent U.S. Pat.No. 4,676,832 as substances which allow mortar mixes to remain fluid,i.e. pumpable for longer, these products being constituted byderivatives of methylenephosphonic acid;

certain others are described in the French Patent FR-A-1 342 412 aswaterproofing and softening agents for textiles when they have highmolecular weights and as complex generators capable of forming chelatingcompounds with multivalent metallic cations when they have lowermolecular weights, the products in question being derivatives of mono-,di- and trialkylenephosphonic acids;

certain others are those described in the French Patent FR-A-1 371 139as substances which complex metallic ions of aqueous solutions or limitprecipitation; these complexing agents aim to improve soaps, shampoos,detergents for textiles or for metals, as well as the polymerization ofrubber and plastic materials and are derivatives ofamino-tris-alkylidene-phosphonic acid;

certain others are those described in the French Patent FR-A-1 376 001as deflocculants and dispersants to improve the rheology of dispersedsystems, the effectiveness being measured for example by viscositymeasurements of kaolin aqueous pastes, the products in question beingsalts of alkylaminopolyalkylenephosphonic acids andalkyl-poly-alkyleneamine-polyalkylene-phosphonic acids;

certain others are those described in the French Patent FR-A-1 399 074as substances which are useful as complexing agents of metallic cationssuch as iron (Fe 111), as deflocculants for drilling fluids for oilwells, as liquefiers for aqueous dispersions of kaolin; these productsare salts of aminotri-alklyenephosphonic acids;

certain others are those described in the Patent U.S. Pat. No. 3,336,221as substances intended to combat scale, in particular from mineral saltsof alkaline-earth type, in the presence of the carbonate ion, under theinfluence of variations of pH, temperature, pressure or the introductionof additional ions capable of forming insoluble compounds with thosealready present, which hinders heat transfers in the materials scaled inthis way and forms sites which favour the development of bacteria; theseproducts, endowed with a threshold effect, i.e. which would be effectiveat sub-stoichiometric doses relative to the water hardness salts presentclearly below a ratio of 1:1 (expressed in moles), are salts ofaminotrialkylenephosphonic acids,polyalkylene-amine-polyalkylenephosphonic acids andpolyhydroxy-alkyleneamine-polyalkylenephosphonic acids;

certain others are those described in the Patent U.S. Pat. No. 3,368,978as products which are suitable for improving the detergent properties ofcertain washing powders, in particular in laundries, concurrently or incombination with tripolyphosphates; they are derivatives ofamino-tris-(alkylidenephosphonic acid) acids;

certain others are those described in the French Patent FR-A-1 458 566as products for the production of washing bars, or auxiliary agents forwashing; they are alkylenepolyphosphonic acids andpolyalkyleneamine-polyalkylenephosphonic acids;

certain others are those described in the Patent U.S. Pat. No. 3,434,969as products having several amino-methylene-phosphonic groups, with atleast three nitrogenous sites linked by --CH₂ -- bonds ("methylene")capable of inhibiting the formation of scale of carbonate and sulphatetype of alkaline-earth ions in the aqueous solutions even at relativelyhigh temperature, exhibiting a threshold effect; these products arealkylamino or polyalkylene-polyamine-(polyalkylenephosphonic) acidsalts;

certain others are those described in the Patents U.S. Pat. No.3,886,204 and U.S. Pat. No. 3,886,205 as products capable of formingcomplexes with alkaline-earth ions; they are derivatives ofalkyl-polycarboxy-phosphonic acid salts;

certain others are those described in the British Patent No. 2 157 279as products capable of retarding the setting of cement during theinjection of hydraulic cement into the soil, or during the mixing ofplaster, they are derivatives of alkylamino orpolyalkylene-polyamine-(polyalkylenephosphonic) acid salts.

The methods of preparing the products in question are described in theprevious patents which have just been described.

As can be noted, the known applications of the products or adjuvants inquestion in no way allow to forecast the potentializing effect which ismanifested when they are used in conjunction with ethephon in accordancewith the process or with the composition according to the invention.

This effect is even more unexpected as it is manifested under verydifferent conditions of use, even antagonistic, to those under which thealready known properties of said products appear.

In this respect, the agricultural plant protection mixtures based on thecomposition according to the invention are applied at ambienttemperature, whilst the scale inhibitors essentially function duringtemperature changes of the medium where they are used; in addition,their activity is only noticeable at alkaline pH's, or when they becomealkaline (in the best case a pH of 4 according to the French PatentFR-A-1 371 139), while in order to retain the stability of ethephon inthe composition according to the present invention, the pH is limited toa maximum of 3.0; similarly, the cements and plasters and the detergentsfor textiles are alkaline; furthermore, the dispersant properties whichcharacterize certain of these products for example in the kaolindispersions, have no use within the scope of the present invention, andcannot explain the action of these same products as an "adjuvant" ofethephon since the final aqueous solutions employed in accordance withthe invention are homogenous and isotropic solutions.

The compositions according to the invention can be used in all formswhich are compatible and acceptable for agronomy.

Concentrated aqueous solutions are particularly convenient to produce,taking into account the good solubility in water, in general, of thedifferent constituents, but gelified aqueous solutions can also beproduced in order to avoid splashing during handling or to obtain ananti-drift effect on the plant protection mixture: in this way thepossibility of the sprayed product being carried by the wind is limited.

The following can be added to it: antifreeze, emollients, dampnessretaining agents, fixing agents for anti-leaching by rain or dew,non-ionic and/or anionic wetting agents, such as, for example,ethyleneglycol, glycerol, fatty alcohols and polyoxyalkylenatedalkylphenols, alkylglucosides, as well as alkylsulphonates andalkylarylsulphonates in acid form or in the form of alkaline saltsprovided that the pH of the formulation does not exceed 3.0.

By adding an aliphatic or aromatic mineral oil, suitably chosenemulsifiers and cosolvants of butylglycol, propyleneglycol, or shortfatty alcohols to the composition according to the present invention,micro-emulsions can be produced.

Soluble powders (i.e. powders in which the active ingredients aresoluble even if the support is insoluble) can also be produced byabsorbing the aqueous solutions of the different constituents on anabsorbent support, which can be soluble in water, such as, for example,a dextrin, or which is insoluble such as, for example, silica; in thelatter case dispersing agents and wetting agents known to a personskilled in the art are added.

The composition according to the invention can also be presented in theform of spreadable granules by impregnating either a calibrated supportproduced from reclaimed papers, for example that marketed under thetrade mark BIODAC®, or a support constituted by a material based onsilicates extracted from deposits and graded, for example that knownunder the designation SEPIOLITE®.

The invention will be better understood by reference to thenon-limitative examples which follow and which relate either toadvantageous implementations of the composition according to theinvention, or to trials showing the effectiveness of the invention.

1. Ethephon-based Compositions

Three compositions according to the invention are prepared; to do thisthe solid substances which dissolve in water are dissolved in water; itis also possible to mix the different aqueous solutions of thesesubstances so as to obtain a final aqueous solution having the desiredproportions.

The various constituents are weighed beforehand to an accuracy of±0.05g.

The solution obtained is decanted quantitatively into a calibrated 100ml flask, then made up to 100 ml and weighed, in this way the densityand the content in g/l of the active ingredients can be calculated.

The products or adjuvants used in the three above-mentioned compositionsare as follows:

1,2,4-butane-tricarboxylic-2-phosphonic acid the formula of which is##STR23## and which is marketed under the trade mark BAYHIBIT AM®,aminotrimethylenephosphonic acid the formula of which is ##STR24## andwhich is marketed under the trade mark DEQUEST 2000®,diethylenetriamine-pentamethylenephosphonic acid the formula of which is##STR25## and which is marketed under the trade mark DEQUEST 2060®.

The other constituents of the three above-mentioned compositions are

an aqueous solution of ethephon at 1000 g/l and known under thedesignation BASE A 250 and containing 72% by weight of ethephon,

an alkylglucoside known under the trade mark TRITON BG 10 and thefunction of which is to confer on the plant protection mixture to beapplied a certain ability to spread over the treated plants.

The three compositions thus prepared are identified as LAB 695, LAB 696and LAB 697 respectively.

The proportions of their different constituents and their propertiesappear in Table I which follows:

                  TABLE I                                                         ______________________________________                                        Compo-                                                                        sition            Weight (g/100 ml)                                                                          Con-                                           desig-                                                                              Type of     of constituents                                                                            tent                                           nation                                                                              constituents                                                                              (content % weight)                                                                         (g/l)                                                                              Remarks                                   ______________________________________                                        Lab 695                                                                             Base A 250  14.0 (72%)   100  density 1.076                                   BAYHIBIT AM 14.0 (50%)   70   easily worked                                   Triton BG 10                                                                              1.0               foam with                                       Water       sqf 100 ml (107.6 g)                                                                            traces of                                                                     silicon                                   Lab 696                                                                             Base A 250  14.0 (72%)   100  density 1.080                                   DEQUEST 2000                                                                              14.0 (50%)   70   easily worked                                   Triton BG 10                                                                              1.0               foam with                                       Water       sqf 100 ml (108.0 g)                                                                            traces of                                                                     silicon                                   Lab 697                                                                             Base A 250  14.0 (72%)   100  density 1.084                                   DEQUEST 2060                                                                              14.0 (50%)   70   easily worked                                   Triton BG 10                                                                              1.0               foam with                                       Water       sqf 100 ml (108.4 g)                                                                            traces of                                                                     silicon                                   ______________________________________                                    

2. Biological Trials in a Greenhouse

Biological trials in a greenhouse were carried out with the threecompositions identified in Example 1.

By way of comparison, a standard solution of ethephon containing 480 g/lof ethephon is used, marketed under the trade mark ETHEREL 48® and whichis designated in what follows by CA 152.

In these trials, the ethylenic activity of the three compositionsstudied is evaluated using a specific test developed on the haricot beanand designated in what follows by "Haricot bean test".

In this test, a batch of haricot plants is treated with the compositionto be studied at the half-open trifoliate second leaf stage.

Four hours after treatment:

the plants are topped above the first trifoliate leaf in order to limitthe growth of the plants; the first retained trifoliated leaf serves toprovide photosynthates;

the limbs of the primary leaves are removed: they are sectioned at theirbase, leaving only the petiole on the plant.

A batch of untreated control plants is prepared in the same way.

Then, the number of petioles which fall is counted, at intervals of oneday and in this way the abscission kinetics induced by each product isestablished.

The absence of petioles falling from the control plants allows thedifferences in the abscission kinetics between the treated batches to beverified which well reflects the differences of activity between theapplied products.

The plants (Cabri haricot bean variety) are cultivated in pots ingreenhouse at a minimal temperature of 13° C.; the day/night cycle is16/8 hours and the relative humidity is about 70%. The compost iscomposed of one third sand, one third peat and one third vegetablemould.

The products are sprayed using a spray-line (under a pressure of 1.5×10⁵Pa); the volume of the plant protection mixture is 1000 1/ha. The doseof ethephon studied is, depending on the trials, 750 or 1000 g perhectare.

For each composition studies, a batch of 20 plants is treated.

All grading is done "blind".

The activity of a regulator is apt to vary as a function of thecultivation conditions. Consequently, the experiments are repeatedseveral times over time in order to validate the results.

a) Series of Trials 1 and 2

In these trials 1 and 2, the ethylenic activity of compositions LAB 695,LAB 696 and LAB 697 is compared to that of standard CA 152. The dose ofthe ethephon studied is 1000 g per hectare.

Trial 1 was carried out in December 1993 and Trial 2 in February 1994.

The results of Trial 1 are set out in Table II.

                                      TABLE II                                    __________________________________________________________________________                  Time of observation (in days) after treatment T                 Dose          T + 2d                                                                            T + 3d                                                                            T + 4d                                                                            T + 5d                                                                            T + 6d                                                                            T + 7d                                                                            T + 8d                                                                            T + 9d                                                                            T + 10d                         Products                                                                           (g of ethephon/ha)                                                                     % of fallen petioles                                            __________________________________________________________________________    Control       0   0    0   0   0   0   0   0  0                               CA152                                                                              1000     0   0   30  63  83  91  100                                     LAB695                                                                             1000     0   0   50  76  91  96   98 100                                 LAB696                                                                             1000     0   4   46  80  91  100                                         LAB697                                                                             1000     0   11  59  89  100                                             __________________________________________________________________________

In the case of the "Control", water is applied without an activeingredient.

The results of trial 2 are set out in Table III.

                                      TABLE III                                   __________________________________________________________________________                  Time of observation (in days) after treatment T                 Dose          T + 2d                                                                            T + 3d                                                                            T + 4d                                                                            T + 5d                                                                            T + 6d                                                                            T + 7d                                                                            T + 8d                                                                            T + 9d                                                                            T + 10d                         Products                                                                           (g of ethephon/ha)                                                                     % of fallen petioles                                            __________________________________________________________________________    Control       0   0   0   0    0   0   0   0   0                              CA152                                                                              1000     0   0   0   0   12  41  62  65  82                              LAB695                                                                             1000     0   0   0   9   24  68  79  88  94                              LAB696                                                                             1000     0   0   0   18  35  76  97  100                                 LAB697                                                                             1000     0   0   0   15  56  91  94  97  100                             __________________________________________________________________________

On examination of the results set out in Tables I and II it is notedthat

the abscission kinetics differ from one product to another; the absenceof leaf-fall in the batches of control plants shows that the differencesobserved are indeed inherent in the differences of activity betweenproducts;

the compositions according to the invention are clearly distinguishedfrom the standard by the following points:

the petiol fall starts earlier after application,

once started, the number of petioles which fall per unit of time isgreater; therefore, at a given observation date after abscission hasstarted, the level of effectiveness is clearly greater (on the third dayfrom starting it is of the order of +20 to +30% in the first trial andof the order of 30 to +50% in the second).

These results show that the ethylenic activity of the compositions basedon ethephon according to the invention is exhibited much more rapidlythan that of the standard and that the level of effectiveness which theyattain is generally greater.

b) Series of Trials 3 to 6

This series of four trials was carried out using the composition LAB697; its purpose is to confirm the results of the first series.

Trials 3 to 6 were carried out respectively

in October 1994, for Trials 3 and 4,

in June 1994, for Trial 5 and

in May 1994, for Trial 6.

In Trials 3 and 4, the dose studies was 750 g of ethephon/ha.

In Trials 5 and 6, it was 1000 g of ethephon/ha.

The results of Trials 3 to 6 are presented in Tables IV to VIIrespectively.

                                      TABLE IV                                    __________________________________________________________________________                  Time of observation (in days) after treatment T                 Dose          T + 2d                                                                            T + 3d                                                                            T + 4d                                                                            T + 5d                                                                            T + 6d                                                                            T + 7d                                                                            T + 8d                                                                            T + 9d                                                                            T + 10d                         Products                                                                           (g of ethephon/ha)                                                                     % of fallen petioles                                            __________________________________________________________________________    Control       0   0   0    0   0   0   0   0   0                              CA152                                                                              750      0   0   2   23  67  90  96  98  100                             LAB697                                                                             750      0   0   15  54  87  94  96  98  100                             __________________________________________________________________________

                                      TABLE V                                     __________________________________________________________________________                  Time of observation (in days) after treatment T                 Dose          T + 2d                                                                            T + 3d                                                                            T + 4d                                                                            T + 5d                                                                            T + 6d                                                                            T + 7d                                                                            T + 8d                                                                            T + 9d                                                                            T + 10d                         Products                                                                           (g of ethephon/ha)                                                                     % of fallen petioles                                            __________________________________________________________________________    Control       0   0   0    0   0   0   0   0  0                               CA152                                                                              750      0   0   2   54  78   91 96  100                                 LAB697                                                                             750      0   4   28  83  98  100                                         __________________________________________________________________________

                                      TABLE VI                                    __________________________________________________________________________                  Time of observation (in days) after treatment T                 Dose          T + 2d                                                                            T + 3d                                                                            T + 4d                                                                            T + 5d                                                                            T + 6d                                                                            T + 7d                                                                            T + 8d                                                                            T + 9d                                                                            T + 10d                         Products                                                                           (g of ethephon/ha)                                                                     % of fallen petioles                                            __________________________________________________________________________    Control       0    0   0   0   0   0  0   0   0                               CA152                                                                              1000     0   16   87 97  97  100                                         LAB697                                                                             1000     3   67  100                                                     __________________________________________________________________________

                                      TABLE VII                                   __________________________________________________________________________                  Time of observation (in days) after treatment T                 Dose          T + 2d                                                                            T + 3d                                                                            T + 4d                                                                            T + 5d                                                                            T + 6d                                                                            T + 7d                                                                            T + 8d                                                                            T + 9d                                                                            T + 10d                         Products                                                                           (g of ethephon/ha)                                                                     % of fallen petioles                                            __________________________________________________________________________    Control       0   0   0   0    0   0   0   0   0                              CA152                                                                              1000     0   0   0   0   11  31  47  56  64                              LAB697                                                                             1000     0   3   33  67  72  92  97  97  97                              __________________________________________________________________________

Examination of the results set out in Tables IV to VII allows thefollowing conclusions to be drawn.

These results:

confirm that the concomitant use of adjuvants and ethephon allows a morerapid and more intense response of plants than ethephon alone,

suggests a lower sensitivity of the proposed specialities to cultivationconditions; in fact, whilst the standard does not achieve the expectedresult in Trial 6, the use of the products according to the inventionallows a very satisfactory level of effectiveness to be achieved.

3. Biological Trials as a Field Crop (on Field)

The effectiveness of the "adjuvants" used concomitantly with ethephon isstudied in the application for the defoliation of cotton (Stonevillevariety) cultivated as a field crop in farmers' plots.

The study is illustrated by Trials 7 and 8. Their location and theircharacteristics are specified in Table VIII.

                  TABLE VIII                                                      ______________________________________                                        Trials           7           8                                                ______________________________________                                        Location         Coria del Rio                                                                             Torre de la reina                                                 Seville, Spain                                                                            Seville, Spain                                   Date of treatment                                                                              19/09/94    13/10/94                                         T° max    27° C.                                                                             31°                                       T° min    19° C.                                                                             22° C.                                    Volume of plant protection                                                                     500 l/ha    500 l/ha                                         mixture                                                                       ______________________________________                                    

The trials are carried out according to a layout in blocks of 3replicates including the control. The basic plots are 32 m² (4 rows of 8m in length).

The composition LAB 697 was studied in comparison to the standard(Ethrel® 48 or CA 152). Each product is applied at the dose of 1200 g ofethephon/ha.

The visual percentage of defoliation of the cotton is evaluated when thetrials are set up, then after treatment regularly every 3 days.

The results of Trials 7 and 8 are set out respectively in Tables IX andX hereafter.

                  TABLE IX                                                        ______________________________________                                        (the results are the average of 3 repeats)                                                             Time of observation                                         Dose              (in days after treatment T                                  (g of ethe-       T + 3d  T + 6d                                                                              T + 9d                                 Products                                                                             phon/ha)   T      % defoliation                                        ______________________________________                                        Control           6.2    16.7    52.5  57.5                                   CA152  1200       7.5    27.5    65.8  78.3                                   LAB697 1200       6.7    33.3    76.7  85                                     ______________________________________                                    

                  TABLE X                                                         ______________________________________                                        (the results are the average of 3 repeats)                                                             Time of observation                                         Dose              (in days after treatment T                                  (g of ethe-       T + 3d  T + 6d                                                                              T + 9d                                 Products                                                                             phon/ha)   T      % defoliation                                        ______________________________________                                        Control                  5       7.5   45                                     CA152  1200              7.5     21.7  69.2                                   LAB697 1200              7.5     26.7  80.8                                   ______________________________________                                    

Examination of the results set out in Tables IX and X allows it to benoted that, if ethephon alone intensifies the defoliation of cottonrelative to the untreated control, the concomitant use of "adjuvants" orproducts used in accordance with the invention allow a clearly moremarked activity to be obtained.

More generally, the observations made both in the greenhouse and infield crops allow the importance of the process and compositionsaccording to the invention to be stated from three points of view:

a) the active ingredient is better enhanced and

a better level of effectiveness can be obtained for the same quantity ofethephon,

the quantity of ethephon applied can be reduced for a given expectedeffect, resulting in a lesser operating cost and a better respect forthe environment,

b) the reduction in time between the treatment and the response allowsthe decision to apply the product to be taken with the shortest ofdelays, which increases the flexibility of use,

c) the lower sensitivity noted for the product as regards climaticcondition extends the times of the year when the product can be used.

We claim:
 1. Ethephon-based composition for the regulation on plant growth containing, in addition to ethephon at least one product or adjuvant the chemical structure of which contains at least two acid functions selected from the group comprising acid functions of carboxylic type of formula (--COOH) and acid functions of phosphonic type of formula (--PO₃ H₂), at least one of these acid functions being the (--PO₃ H₂) function, said product being selected from the group comprisingthat having the formula ##STR26## and those in which the functions are connected by an organic chain of (--R--O--R) type containing an ether function wherein the two chains R are identical to or different from each other.and/or an organic chain of (--R--NH--R) type containing a secondary amine function wherein the two chains R are identical to or different from each other, and/or an organic of ##STR27## type containing two tertiary amine functions wherein the two chains R are identical to or different from each other, and/or by a chain of ##STR28## type in which (--R') represents hydrogen or the afore-mentioned chain R, and/or by an organic chain of ##STR29## type containing a tertiary amine function wherein the three chains R are identical to or different from each other,wherein R represents a linear or branched hydrocarbon chain containing from 2 to 6 carbon atoms and optionally one or more substituents of hydroxyl type (--OH) and/or halogen and/or hydroxethyl (--CH₂ --CH₂ --OH) and/or phenyl (--C₆ H₅) and/or hydroxyphenyl (--C₆ H₄ --OH).
 2. Composition according to claim 1, characterized in that the chemical structure of the product or adjuvant which contains at least two acid functions, is represented by one of the general formulae indicated hereafter: ##STR30## in which n represents an integer from 0 to 4,R₂ represents a linear or branched hydrocarbon group having 2 to 6 carbon atoms, R₁ represents, independently at each occurrence, a hydrogen atom, an alkyl chain having 1 to 4 carbon atoms, a phenyl group, a hydroxyphenyl group, a hydroxyalkyl group, an alkylene-phosphonic acid group or one of the five groups represented below:

    --CH.sub.2 --CH.sub.2 --NH--PO.sub.3 H.sub.2 ##STR31##


3. Composition according to claim 1, characterized in that the chemical structure of the product or adjuvant, which contains at least two acid functions, is represented by the formula in whichn represents an integer equal to 0 or 1, X and Y represent a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, R₃ represents a hydrogen atom, an aliphatic hydrocarbon group, a halo-substituted aliphatic hydrocarbon group, a hydroxy-substituted aliphatic hydrocarbon group, the --CH₂ COOH group or the ##STR32## group in which m represents an integer from 1 to 6, X and Y represent a hydrogen atom or an alkyl group, Z represents a hydrogen atom or the ##STR33## Z' represents Z or the group of formula ##STR34## in which b is an integer from 1 to
 6. 4. Composition according to claim 1, characterized in that the chemical structure of the product or adjuvant, which contains at least two acid functions, is represented by the formula ##STR35## in which R" represents hydrogen or a short alkyl chain having 1 to 4 carbon atoms,R"' represents hydrogen or a methyl group, the products corresponding to formulae ##STR36## as well as ##STR37## being more particularly preferred.
 5. Composition according to claim 1, characterized in that the chemical structure of the product or adjuvant, which contains at least two acid functions, is represented either by the formula ##STR38## in which n is an integer from 1 to 5, or by the following products: 1,6-hexylenediamine-N,N,N',N'tetrakis((methylene)-phosphonic) acid,ethylenediamine-N,N,N',N'-tetrakis((methylene)-phosphonic) acid, diethylenetriamine-N,N,N',N",N"-penta((methylene)-phosphonic) acid, nitrilo-N,N,N-tris((methylene)-phosphonic) acid which are particularly preferred.
 6. Composition according to claim 1, characterized in that the chemical structure of the product or adjuvant, which contains at least two acid functions, is represented by one of the formulae ##STR39##
 7. Composition according to one of claims 1 and 2 to 6, characterized in that the ratio of ethephon/adjuvant by weight is 10/1 to 1/10, preferably 5/1 to 1/5.
 8. Plant growth regulation process comprising applying, on the plants to be treated, ethephon and at least one product, the chemical structure of which is characterized in that it contains at least two acid functions selected from the group comprising acid functions of carboxylic type of formula (--COOH) and acid functions of phosphonic type of formula (--PO₃ H₂), at least one of these acid functions being the (--PO₃ H₂) function, said product being selected from the group comprising that having the formula: ##STR40## and those in which the acid functions are connected by an organic chain of (--R--O--R) type containing an ether function wherein the two chains R are identical to or different from each other,and/or an organic chain of (--R--NH--R) type containing a secondary amine function wherein the two chains R are identical to or different from each other, and/or an organic chain of ##STR41## type containing two tertiary amine functions wherein the two chains R are identical to or different from each other, and/or by a chain of ##STR42## type in which (--R') represents hydrogen or the aforementioned chain R, and/or by an organic chain of ##STR43## type containing a tertiary amine function wherein the three chains R are identical to or different from each other,wherein R represents a linear or branched hydrocarbon chain containing from 2 to 6 carbon atoms and optionally one or more substituents of hydroxyl type (--OH) and/or halogen and/or hydroxyethyl (--CH₂ --CH₂ --OH) and/or phenyl (--C₆ H₅) and/or hydroxyphenyl (--C₆ H₄ --OH).
 9. Process according to claim 8, characterized in that 20 g to 3000 g of ethephon and 20 g to 5000 g of one or more adjuvants according to one of claims 1 and 2 to 6 are applied per hectare.
 10. Process for plant growth regulation characterized in that an effective quantity is applied to the plants to be treated depending on the cultivation, the physiological stage and the effect sought, preferably from 20 to 3000 g of ethephon and preferably 20to 5000 g of one or more adjuvants according to one of claims 1 and 2 to
 6. 11. Process according to claim 10, characterized in that the composition is preferably applied in the form of a plant protection mixture containing 20 g to 3000 g of ethephon and 20 to 5000 g of adjuvant according to one of claims 1 and 2 to 7, the whole being dissolved in 20 to 3000 litres of water. 